1. Field of the Invention
This invention relates to a system including an image capturing section and an image-information transmitting section.
2. Description of the Related Art
It is conceivable to provide first and second imaging devices, and to transmit image information pieces from the first and second imaging devices to a common network. Such a conceivable system includes first and second timing signal generators, and first and a second drive circuits for the first and second imaging devices respectively. The first drive circuit operates the first imaging a device in response to an output signal of the first timing signal generator. The second drive circuit operates the second imaging device in response to an output signal of the second timing signal generator.
The conceivable system also includes first and second signal processors, and first and second transmitters. The first signal processor converts an output signal of the first imaging device into first video data. The first transmitter encodes the first video data into a first stream of packets. The first transmitter outputs the first packet stream to the network while using a first band and a first channel. On the other hand, the second signal processor converts an output signal of the second imaging device into second video data. The second transmitter encodes the second video data into a second stream of packets. The second transmitter outputs the second packet stream to the network while using a second band and a second channel different from the first band and the first channel.
The conceivable system tends to be complicated in structure since there are the two timing signal generators, the two drive circuits, and the two transmitters.
It is an object of this invention to provide an image capture and transmission system having a simple structure.
A first aspect of this invention provides an image capture and transmission system comprising first and second imaging devices; first means for generating a timing signal; a common drive circuit for driving the first and second imaging devices at equal timings determined by the timing signal generated by the first means; a first signal processor for converting an output signal of the first imaging device into first digital video data; a second signal processor for converting an output signal of the second imaging device into second digital video data; second means for processing the first digital video data and the second digital video data into a stream of packets; and third means for transmitting the packet stream generated by the second means.
A second aspect of this invention is based on the first aspect thereof, and provides an image capture and transmission system further comprising a third imaging device, and a drive circuit for driving the third imaging device at a timing different from the timings of drive of the first and second imaging devices.
A third aspect of this invention is based on the first aspect thereof, and provides an image capture and transmission system wherein the third means comprises means for outputting the packets in the stream to a network, and the first means comprises means for generating the timing signal synchronized with the outputting of the packets to the network.
A fourth aspect of this invention is based on the first aspect thereof, and provides an image capture and transmission system further comprising means for setting a changeable transmission start point in every frame represented by the first digital video data and the second digital video data, and means for enabling the transmission of the first digital video data and the second digital video data in the packet stream by the third means to start at the transmission start point for every frame represented by the first digital video data and the second digital video data.
A fifth aspect of this invention is based on the first aspect thereof, and provides an image capture and transmission system further comprising means provided in the third means for re-transmitting a portion of the packet stream in response to a signal of a re-transmission request.
A sixth aspect of this invention is based on the first aspect thereof, and provides an image capture and transmission system further comprising means provided in the third means for re-transmitting a whole of the first digital video data and the second digital video data in the packet stream.
A seventh aspect of this invention is based on the first aspect thereof, and provides an image capture and transmission system wherein the second means comprises means for compressing the first digital video data into first compression-resultant digital video data, means for compressing the second digital video data into second compression-resultant digital video data, and means for combining the first compression-resultant digital video data and the second compression-resultant digital video data into the packet stream.
An eighth aspect of this invention is based on the first aspect thereof, and provides an image capture and transmission system wherein the second means comprises means for executing a first calculative operation between the first digital video data and the second digital video data, and generating first operation-resultant digital video data, means for executing a second calculative operation between the first digital video data and the second digital video data, and generating second operation-resultant digital video data, the second calculative operation being different from the first calculative operation, means for compressing the first operation-resultant digital video data into first compression-resultant digital video data, means for compressing the second operation-resultant digital video data into second compression-resultant digital video data, and means for combining the first compression-resultant digital video data and the second compression-resultant digital video data into the packet stream.
A ninth aspect of this invention is based on the first aspect thereof, and provides an image capture and transmission system wherein the second means comprises means for setting a changeable effective region in every frame represented by the first digital video data and the second digital video data, means for selecting portions of the first digital video data and the second digital video data which correspond to the effective region in every frame, and means for placing only the selected portions of the first digital video data and the second digital video data in the packet stream.
A tenth aspect of this invention is based on the ninth aspect thereof, and provides an image capture and transmission system wherein the effective region in every frame is rectangular, and extends between horizontal limit positions and extends between vertical limit positions.
An eleventh aspect of this invention is based on the ninth aspect thereof, and provides an image capture and transmission system further comprising means for searching every frame represented by the first digital video data and the second digital video data for a predetermined target object, and means for changing the effective region in every frame in response to a result of the searching.
A twelfth aspect of this invention is based on the ninth aspect thereof, and provides an image capture and transmission system further comprising means for sensing a specified object in every frame represented by the first digital video data and the second digital video data, and generating information of a result of the sensing, means provided in the second means for automatically setting the effective region in every frame in accordance with a variable setting condition, and means for deciding the setting condition in response to the information of the result of the sensing.
A thirteenth aspect of this invention is based on the ninth aspect thereof, and provides an image capture and transmission system further comprising means for sensing a specified object in every frame represented by the first digital video data and the second digital video data, and generating information of a result of the sensing, and means for changing the effective region in every frame in response to the information of the result of the sensing.